Bleaching agents and additives

ABSTRACT

THE INVENTION RELATES TO NOVEL N-HALO-N-ALKYL-O-SULFOBENZAMIDES. THESE COMPOUNDS ARE USEFUL IN BLEACHING COMPOSITIONS AND METHODS. SOME ARE ACTIVATORS FOR PEROXYGEN BLEACHING AGENTS, AND SOME HAVE BLEACHING ACTIVITY THEMSELVES.

United States Patent 3,706,671 BLEACHING AGENTS AND ADDITIVES FrederickEdward Hardy, Newcastle-upon-Tyne, England,

assignor to The Procter & Gamble Company, Cincinnati, Ohio No Drawing.Original application Apr. 2, 1970, Ser. No. 25,292. Divided and thisapplication Feb. 3, 1972, Ser.

Int. Cl. C11d US. Ci. 252-99 9 Claims ABSTRACT OF THE DISCLOSURE Theinvention relates to novel N-halo-N-alkyl-o-sulfobenzamides. Thesecompounds are useful in bleaching compositions and methods. Some areactivators for peroxygen bleaching agents, and some have bleachingactivity themselves.

This application is a division of US. patent application Ser. No.25,292, now US. Pat. No. 3,652,660.

BACKGROUND OF THE INVENTION Detergent and bleaching compositionscontaining peroxygen bleaches, most commonly sodium perborate, have longbeen known. They suffer from the disadvantage that perborate has limitedbleaching activity at washing temperature below about 85 C. Variousorganic N-chloro and N-bromo compounds have also been known, and someare low temperature effective bleaches, but they have not been widelyused in detergent compositions as they tend to be somewhat harsh intheir effect upon fabrics and may give an undesirable chlorine-type odorin use. If attempts are made to use peroxygen and chlorobleachestogether, they are generally found to cancel each others effect, in thatreaction occurs between them with the liberation of molecular oxygenwhich has no appreciable bleaching effect.

SUMMARY OF THE INVENTION The present invention provides newN-halo-N-alkyl-osulfobenzamides of the formula:

wherein X is chlorine and bromine, R is an alkyl group and M is acation.

M is preferably an alkali metal or alkaline earth metal ion.

The alkyl group R generally has from 1 to 20 carbon atoms, andpreferably is either a short chain group of 1 to 4 carbon atoms or,especially if surface-active compounds are desired, a relatively longchain group of to 18 carbon atoms.

N-chloro compounds are valuable in particular as activators forperborate and like compounds, so that these become effective bleachingagents at temperatures below about 85 C., for instance in the range fromabout 38 C. to about 82 C. and especially in the range from about 49 C.to about 60 C. The N-chloro compounds generally have little or nobleaching activity on their own and cause little or no chlorine-typeodor in use. Some, at least, of the N-bromo compounds are bleachingagents in their own right, and are generally too reactive to be suitableas activators for peroxy compounds. Both the N-chloro and the N-bromocompounds have bactericidal properties. Those compounds whose alkylgroup R is of chain length usual in surface active agents, for instance3,706,671 Patented Dec. 19, 1972 DETAILED DESCRIPTION OF THE INVENTIONThe compounds of this invention can be prepared by any effective method.A convenient starting material is o-sulfobenzoic anhydride, which istreated with an amine RNH (where R is the alkyl group of the intendedcompound) in the presence of an amine. The amine salt of the resultingN-alkyl-o-sulfobenzamide is converted to the alkali or alkaline earthmetal sulfonate salt and this is chlorinated or brominated by treatmentwith hypochlorous or hypobromous acid.

The N-chloro compounds of the invention are useful as activators forinorganic peroxygen compounds, such as alkali metal perborates,percarbonates and other salts which release hydrogen peroxide in aqueoussolution. They may be used in most solid, especially granular solid,compositions containing such peroxy compounds. Many such compositions,often containing from about 5 to about 35% sodium perborate, are knownin the art. Enough (but normally not substantially more than enough) ofthe N-chloro compound should be included to provide an appreciable andsufficient activating effect, and good results have been obtained whenthe molar ratio of activator to peroxy compound is from about 1:20 to1:1, especially from about 1:10 to 1:15.

The N-bromo compounds are bleaching agents in their own right and aresuitable for use in the formulation of granular bleaching compositions,conveniently by mixing them with organic or inorganic builder salts,water-soluble organic surface active agents or mixtures thereof.

Alkaline builder salts which can be used in conjunction with theN-chloro and N-bromo compounds of the invention include the organic andinorganic builder salts such as sodium pyrophosphate, sodiumtripolyphosphate, trisodium and disodium orthophosphates, sodiumcarbonate, sodium sesquicarbonates, sodium bicarbonate, various sodiumsilicates, sodium aminopolycarboxylates such as sodium ethylene diaminetetraacetates, sodium ethane-1,1- diphosphonates and the like. Manyother inorganic alkaline, neutral or acidic salts may be included asfillers or for processing reasons.

The corresponding salts of other alkali metals, for instance potassium,may be substituted for part or all of the sodium salts.

In bleaching compositions containing an N-bromo compound of theinvention, the N-bromo compound can constitute from about 1% to about ofthe total composition. Generally it is included in an amount whichprovides from about 1% to 18%, preferably about 5% by weight ofavailable bromine in the composition.

The meaning of the term percent available bromine is defined by analogywith the term percent available chlorine as applied to chlorinebleaching agents. The latter term represents the percentage by weight ofmolecular chlorine (C1 having equal bleaching power. Since one atom ofactive chlorine in an N-chloro compound and in hypochlorites has thesame activity as one molecule of molecular chlorine (i.e., two atoms)the percentage available chlorine stated is, by weight, twice thepercentage of active chlorine in the compound or composition, andcorrespondingly the percentage of available bromine is twice thepercentage of active bromine. Thus, sodiumN-bromo-N-methyl-o-sulfobenzamide monohydrate contains 21.8% (active)bromine by weight, which is expressed as 43.6% available bromine.

Detergent compounds which can be employed in conjunction with theN-chloro and N-bromo compounds of the invention include Water-solubleorganic detergents such as soap, anionic synthetic detergents, andnonionic, zwitterionic and cationic detergents. Preferred compositionsare based on soaps or anionic sulfonate or sulfate detergents, such asalkyl benzene sulfonates, alkyl sulfates, olefine sulfonates and manyothers well known in the art. Often nonionic detergents such as fattyalcohol-or alkylphenol-ethylene oxide condensates, fatty acidalkanolamides and the like are also incorporated. The usual minorcomponents of detergent compositions may also be present such as sudsboosters or depressants, soil suspending agents, corrosion inhibitors,bleach-stable optical brighteners, colors and perfume materials. Asuitable ratio of water-soluble detergent to builder salt is from 10:1to 1: 10, and preferably from 1:1 to 1:5.

The N-halo compounds of the invention can also be used for the purposesdescribed above in abrasive or other hard surface cleansers. They havegood bactericidal properties and may be used in dishwashing compositionsfor use in automatic dishwashing machines.

The invention is illustrated by the following examples:

EXAMPLE I Sodium N-chloro-N-methyl-o-sulfobenzamideN-methyl-o-sulfobenzamide was prepared by reacting o-sulfobenzoicanhydride with methylamine and treating the resulting amine salt withAmberlite IR 120 (H+) resin. 32.6 g. of the N-methyl-o-sulfobenzamidewere dissolved in 200 ml. of water and the solution was neutralized withsodium hydroxide. 480 ml. of 0.42 molar hypochlorous acid (fromdistillation of a mixture of commercial sodium hypochlorite and boricacid) were added and the mixture was stored for 3 hours at roomtemperature and then overnight at 4 C. On evaporation of the solution toa small volume the N-chloro body crystallized. This material (39.4 g.)was filtered and dried. On analyzsis there was found: C, 33.25%; H,3.2%; N, 4.75%.

C3H7C1NN304S, H O requires C, 33.15%, H, 3.1%; N, 4.85.

EXAMPLE II Sodium N-bromo-N-methyl-o-sulfobenzamide 5 g. of the acidN-methyl-o-sulfobenzamide as prepared in Example I were dissolved in 50m1. of water and the solution was neutralized with sodium hydroxide. 150ml. of 0.16 molar hypobromous acid (prepared by treating bromine waterwith mercuric oxide and distilling the filtrate) were added and themixture was stored at room temperature for two hours. Evaporation todryness gave the N-bromo body (7.3 g.) in microcrystalline form. Onanalysis there was found: C, 28.1%; H, 2.65%; N, 3.9%. C H BrNNaO S,H Orequires C, 28.75%; N, 4.2%.

EXAMPLE III Sodium N-chloro-N-hexadecyl-o-sulfobenzamide 3 g. ofo-sulfobenzoic anhydride were added to a solution of 3.9 g. ofhexadecylamine and 2.5 ml. of triethylamine in 40 ml. of anhydrousbenzene. The mixture -was heated under reflux for 3 hours and stored atroom temperature overnight. Evaporation to dryness gave triethylammoniumN-hexadecyl-o-sulfobenzamide, which was recrystallized from ethanol. Theyield was 7.9 g.

This salt was dissolved in ethanol-water (1:9) and converted to the freesulfonic acid by treatment with Amberlite IR 120 (H resin.Neutralization with sodium hydroxide followed by evaporation to drynessgave the corresponding sodium salt which was recrystallized fromacetone. This material (5 g.) was suspended in 125 ml.

EXAMPLE IV A control washing solution (A) was prepared containing 0.5%by weight of the following detergent-bleaching composition (theproportions being by weight).

Linear alkyl benzene sulfonate 14.0 Sodium toluene sulfonate 1.4 Sodiumtripolyphosphate 36.7 Sodium silicate 5.8 Coconut monoethanolamide 1.5

Sodium perborate tetrahydrate 20.5

Sodium carboxymethyl cellulose 0.8 Sodium sulfate 9.5 Perfume,brightener, minor components, etc 1.8 Moisture 8.0

A solution (B) contained in addition 5% and a solution (C) contained20%, by weight of the detergent composition, of the compound of theformula:

CON(GH;)G1

CeH4

SO Na These proportions correspond to 14 and 56 molar percentrespectively, referred to the perborate.

Standard tea stained cloth swatches were treated in the solutions andthe percentage stain removal measured. Three test conditions wereemployed:

(i) 10 minutes agitation at 49 C.,

(ii) 16 hours soaking beginning at 49 C. and allowing to cool naturallyto room temperature,

(iii) heating over a period of 1 hour from 49 C. to 82 C. and thenagitating for 10 minutes.

Percentage stain removal figures are given below:

Solution A B 0 Washing condition:

Comparison of the results for solutions of compositions of the inventionB and C with the control solution A show the activating effect of thecompounds of the invention, which is as would be expected more marked inconditions 1 and 2 than in condition 3 Where the temperature approachedthat at which perborate alone is known to become fully effective.

EXAMPLE V A washing solution containing 5 g. per liter of the detergentcomposition of Example IV with the sodium perborate omitted was preparedcorresponding to solution A above. To one part was added a sample ofsodium N- bromo-N-methyl-o-sulfobenzamide in amount to provide 0.22 g.per liter available bromine, thus forming a solution D. To another partwas added a sample of N-bromo benzenesulfonamide (the prior knownbleaching agent, commonly named Bromamine-B) in amount to provide thesame proportion of available bromine, thus forming a solution B.

When used to wash standard tea-stained cloth swatches for 10 minutes at49 C. solution D gave 86% stain removal, and solution B gave 57% stainremoval.

When used at equivalent concentration in this test procedure thecorresponding N-chloroN-methyl-o-sulfobenzamide gave stain removalresults indistinguishable from those given by the detergent compositionin the absence of bleaching agent, viz about 20 to 25%.

What is claimed is:

1. A bleaching composition consisting essentially of comprising aninorganic per-oxygen compound; and an N- chloro-N-alkyl-o-sulfobenzamideof the formula SOaM wherein'R is alkyl of from 1 to about 20 carbonatoms and M is a cation.

2. The composition of claim 1 wherein the molar ratio of said inorganicperoxygen compound and said N-chloro- N-alkyl-o-sulfobenzamide is from1:20 to 1:1.

3. The composition of claim 2 wherein the inorganic peroxygen compoundis sodium perborate.

4. The composition of claim 3 wherein a mixture of water-soluble organicdetergent and builder salt is present; the ratio of said water-solubleorganic detergent to said builder salt is from 10:1 to 1:10.

5. A bleaching composition consisting essentially of a mixture ofwater-soluble detergent and builder salt; and from about 1% to about 90%of a compound of the formula wherein R is alkyl of from 1 to about 20carbon atoms and M is a cation.

6. The composition of claim 5 wherein the available bromine is from 10%to 18% by weight of the composition.

7. The composition of claim 6 wherein R is alkyl of from 1 to 4 carbonatoms and M is sodium.

8. A process of bleaching textile fabrics which comprises treating saidfabrics in an aqueous medium with the composition of claim 1.

9. A process of bleaching textile fabrics which comprises treating saidfabrics in an aqueous medium with the composition of claim 5.

References Cited UNITED STATES PATENTS 2,076,217 4/1937 Albrecht 260-507MAYER WEINBLATT, Primary Examiner US. Cl. X.R.

